Quality of Service in Optical Packet Switched Networks - Akbar G. Rahbar - E-Book

Quality of Service in Optical Packet Switched Networks E-Book

Akbar G. Rahbar

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This book is a comprehensive study on OPS networks, itsarchitectures, and developed techniques for improving its qualityof switching and managing quality of service. The bookincludes: * Introduction to OPS networks, OOFDM networks, GMPLS-enabledoptical networks, QoS in OPS networks * Hybrid contention avoidance/resolution schemes in bothlong-haul and metro optical networks * Hybrid optical switching schemes

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IEEE Press

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IEEE Press Editorial Board

Tariq Samad, Editor in Chief

George W. Arnold

Vladimir Lumelsky

Linda Shafer

Dmitry Goldgof

Pui-In Mak

Zidong Wang

Ekram Hossain

Jeffrey Nanzer

MengChu Zhou

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Ray Perez

George Zobrist

    Kenneth Moore, Director of IEEE Book and Information Services (BIS)

QUALITY OF SERVICE IN OPTICAL PACKET SWITCHED NETWORKS

Akbar Ghaffarpour Rahbar

Sahand University of Technology

Copyright © 2015 by The Institute of Electrical and Electronics Engineers, Inc.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey. All rights reserved. Published simultaneously in Canada.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permission.

Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

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Library of Congress Cataloging-in-Publication is available.

ISBN 978-1-118-89118-6

To my parents and my family

CONTENTS

PREFACE

REFERENCES

ACKNOWLEDGMENTS

ACRONYMS

GLOSSARY

SYMBOLS

CHAPTER 1 INTRODUCTION TO OPTICAL PACKET SWITCHED (OPS) NETWORKS

1.1 Optical Fiber Technology

1.2 Why Optical Networks?

1.3 Optical Networking Mechanisms

1.4 Overview of OPS Networking

1.5 Optical OFDM-Based Elastic Optical Networking (EON)

1.6 Summary

References

CHAPTER 2 CONTENTION AVOIDANCE IN OPS NETWORKS

2.1 Software-Based Contention Avoidance Schemes

2.2 Hardware-Based Schemes

2.3 Formulation of Even Traffic Transmission in Slotted OPS

2.4 Summary

References

CHAPTER 3 CONTENTION RESOLUTION IN OPS NETWORKS

3.1 Hardware-Based Contention Resolution Schemes

3.2 Software-Based Contention Resolution Schemes

3.3 Summary

References

CHAPTER 4 HYBRID CONTENTION AVOIDANCE/RESOLUTION IN OPS NETWORKS

4.1 Hybrid Contention Resolution Schemes

4.2 Hybrid Contention Resolution and Avoidance Schemes

4.3 Summary

References

CHAPTER 5 HYBRID OPS NETWORKS

5.1 Hybrid Asynchronous and Synchronous OPS Networks

5.2 Hybrid OPS and OCS Networks

5.3 Comparison of Hybrid OPS Schemes

5.4 Summary

References

CHAPTER 6 METRO OPS NETWORKS

6.1 OPS in Star Topology

6.2 OPS in Ring Topology

6.3 Summary

References

Index

IEEE Press Series on Information and Communication Networks Security (ICNS)

EULA

List of Tables

Chapter 2

Table 2.1

Table 2.2

Table 2.3

Table 2.4

Table 2.5

Chapter 3

Table 3.1

Table 3.2

Table 3.3

Table 3.4

Chapter 4

Table 4.1

Table 4.2

Table 4.3

Table 4.4

Table 4.5

Table 4.6

Chapter 6

Table 6.1

Table 6.2

Table 6.3

Table 6.4

Table 6.5

Guide

Cover

Table of Contents

Preface

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PREFACE

Welcome to the era of unlimited communications, video-centric applications, and Internet! Internet applications require both bandwidth and Quality of Service (QoS) because of a huge number of Internet users and growing number of real-time applications (such as 3D TV, ultrahigh-definition TV, video-on demand, Internet Protocol TeleVision (IPTV), video-conferencing, Internet gaming, voice over IP, etc.) that need different levels of QoS. IP networks consist of core networks and access networks. By increasing IP traffic, access networks can grow in both size and count [1]. For example, traffic of broadband access networks such as ADSL and Fiber To The Home (FTTH) is continually increasing every year. To transport the huge traffic offered by IP networks, the core networks capabilities must be increased to avoid them from becoming bottleneck for IP traffic. This could be a problem when the network bandwidth is limited, the network supports only the best effort traffic, and the Internet traffic does not have a uniform characteristic.

The need for more and more bandwidth forces us to think of more granularity. The best promising solution is to use Wavelength Division Multiplexing (WDM) all-optical networks in core networks. Note that an optical network that uses optical transmission and keeps optical data paths through the nodes from source to destination is called all-optical network. Due to the fact that all-optical networks use photonic technology for the implementation of both switching and transmission functions, signals in these networks can be maintained in optical form without any conversion to the electronic domain resulting in much high transmission rates. All-optical networking with deployment of Dense Wavelength Division Multiplexing (DWDM) appears to be the sole approach to transport the huge network traffic in future backbone networks. The DWDM technology provides the multiplexing of many wavelength channels in a single optical fiber, resulting in several Tbits/s bandwidth capacity.

Similar to the electronic domain in which packet switching is the most granular method of switching, the most promising technique for optical core networks could be Optical Packet Switching (OPS) due to its high throughput and very good granularity and scalability. In an OPS edge node, a header is attached to each client packet received from a legacy network, where the header includes the information about source edge node, destination edge node, and content of packet payload such as its length. The packet is then transmitted in the optical domain, called an optical packet, toward the OPS network. In OPS, an optical packet stays in the optical domain inside the core network and switched optically. The optical packet can only be converted to the electronic domain in its destination edge node. Packet switching provides connectionless transmission of packets. Thus, there is no need to establish a path (i.e., a circuit) between source-destination nodes like in circuit switching. However, contention of optical packets in the core network is the major problem in OPS networks.

Since different applications need different levels of QoS, service differentiation must be considered in optical networks as well. Under the best-effort service in which no guarantees are given to any packet regarding loss rate, delay, and delay jitter, all traffic in the network is equally treated. This will, in turn, degrade the QoS requirements for real-time traffic. Thus, having a QoS-capable optical backbone network will be a requirement in which low latency, low jitter, low loss, and bandwidth guarantees must be provided for real-time traffic.

For providing QoS in OBS networks, [2] details (a) the basic mechanisms developed for improving end-to-end QoS and (b) relative and absolute QoS differentiation among multiple service classes. On the other hand, for OCS networks, the work in [3] focuses on the methods developed for service-differentiated and constraint-based wavelength routing and allocation in multi-service WDM networks. However, there is no comprehensive work on QoS in OPS networks.

In future, OPS networks must be setup for worldwide communications in order to transport the huge traffic generated by Internet users and applications. In addition, research and development on optical communication networking have been matured significantly during the last decade to the extent that some of these principles have moved from the optical research laboratories to formal graduate courses. Moreover, there are a large number of experts working on designing optical devices and physical-layer of optics that are interested in learning more about OPS network architectures, protocols, and the corresponding engineering problems in order to design new state-of-the-art OPS networking products. Finally, there are many books written for device level of optical communications, and there are even devices suitable for OPS. However, there is almost no work dedicated solely for system level of OPS (say architectures and protocols), improving quality of service, and the operation of OPS networks.

In general, there are some books published for covering optical networking such as [4-10]. However, the number of published books dedicated to the system level of OPS is limited to OPS in access networks [11], design of optical buffers for OPS [12], edge node design for contention avoidance in slotted OPS [13], scheduling in star-based OPS networks [14], and OPS for ring networks [15].

This book provides a comprehensive study on OPS networks, its architectures, and developed techniques for improving its quality of switching and managing quality of service. This book is organized in six chapters, each covering a unique topic in detail:

Chapter 1 provides an introduction to OPS networks, its architectures, and QoS in OPS. Since many optical networking books have stated optical systems in much detail, this chapter does not include them. In addition to OPS networks, GMPLS-supported optical networks and optical networks based on Orthogonal Frequency Division Multiplexing (OOFDM) are studied in this chapter.

Chapter 2 describes contention avoidance schemes proposed for OPS networks in which edge switches send optical packets to the OPS network in a way to reduce their collisions. Broadly, these schemes are classified as either hardware-based or software-based.

Chapter 3 details contention resolution schemes proposed for OPS networks in which OPS switches resolve the collision of contenting optical packets. In general, contention resolution schemes are classified as either hardware-based or software-based.

Chapter 4 studies the hybrid contention resolution schemes that use a number of contention resolution schemes in the same architecture in order to reduce optical packet loss rate. In addition, hybrid contention resolution and contention avoidance schemes are reviewed that can efficiently reduce optical packet loss rate in a cost-effective manner.

Chapter 5 describes hybrid optical switching schemes in which OPS networking is combined with another optical switching technique (say optical circuit switching) in order to improve the performance of traffic transmission in the optical domain.

Chapter 6 states different OPS architectures designed for metro area. These networks are mainly based on ring and star topologies with active optical switches.

This book is a useful resource for students, engineers, and researchers to learn more about optical packet switched networking from system level points of view. It is intended as a textbook for graduate level and senior undergraduate level courses in electrical engineering and computer science on (advanced) optical networking. Knowledge about computer networks is a prerequisite for understanding this book. For advanced optical networks course relevant to OPS, the book can be entirely used.

Reasonable care has been taken in eliminating any types of errors. However, readers are encouraged to send their comments and suggestions to the author via e-mail. I personally hope that this book will give the reader enough information in OPS networks and motivate his/her interests to develop efficient, QoS-capable, and cost-effective OPS networks suitable for future core optical networks.

AKBAR GHAFFARPOUR RAHBAR

Sahand University of Technology [email protected]

REFERENCES

A. Shami, M. Maier, and C. Assi.

Broadband Access Networks: Technologies and Deployments

. Springer, 2009.

K. C. Chua, M. Gurusamy, Y. Liu, and M. H. Phung.

Quality of Service in Optical Burst Switched Networks

. Springer, 2007.

A. Jukan.

QoS-based Wavelength Routing in Multi-Service WDM Networks

. Springer, 2001.

B. Mukherjee.

Optical WDM Networks

. Springer, 2006.

R. Ramaswami, K. Sivarajan, and G. Sasaki.

Optical Networks: A Practical Perspective

. third edition, Morgan Kaufmann, 2009.

T. E. Stern, G. Ellinas, and K. Bala.

Multiwavelength Optical Networks: Architectures, Design, and Control

. second edition, Cambridge University Press, 2008.

J.M. Simmons.

Optical Network Design and Planning

. Springer, 2008.

V. Alwayn.

Optical Network Design and Implementation

. Cisco Press, 2004.

R. J. B. Bates.

Optical Switching and Networking Handbook

. McGraw-Hill, 2001.

M. Maier.

Optical Switching Networks

. Cambridge University Press, 2008.

K. Bengi.

Optical Packet Access Protocols for WDM Networks

. Springer, 2002.

E. H. Salas.

Design of Optical Buffer Architectures for Packet-Switched Networks: An Optical Packet Buffer Overview

. LAP Lambert Academic Publishing, 2010.

A. G. Rahbar and O. Yang.

OPS Networks: Bandwidth Management & QoS

. VDM Verlag, Germany, 2009.

N. Saberi.

Photonic Networks: Bandwidth Allocation and Scheduling

. LAP LAMBERT Academic Publishing, 2011.

B. Uscumlic.

Optical Packet Ring Engineering: Design and Performance Evaluation

. LAP LAMBERT Academic Publishing, 2011.

ACKNOWLEDGMENTS

To all those wonderful people I owe a deep sense of gratitude especially now that this book has been completed. To my wife and daughter for their consistent patience and encouragement. To the publisher’s staff for their collaboration and project management.

Akbar Ghaffarpour Rahbar

ACRONYMS

3LIHON

3 Level Integrated Hybrid Optical Network

ACK

ACKnowledge

AF

Assured Forwarding

APTB

Aggregated Packet Transmission Buffer

AW

Additional Wavelengths

AWG

Array Waveguide Grating

BE

Best Effort

BER

Bit Error Rate

BH

Burst Header

BP

Buffer Pool

bps

bits per second

BPSK

Binary Phase-Shift Keying

BV

Bandwidth Variable

BvN

Birkhoff and von Neumann

CBR

Constant Bit Rate

COPS

Composite Optical Packet Scheduling

CoS

Class of Service

CPA

Composite Optical Packet Aggregation

CPDU

Control packet PDU

CRSA

Contention Resolution Scheduling Algorithm

CSMA/CA

Carrier Sense Multiple Access with Collision Avoidance

CWDM

Coarse WDM

DA

Distribution-based bandwidth Access

DCF

Dispersion Compensated Fiber

DiffServ

Differentiated Services

DMUX

DeMultiplexer

DR

Deflection Routing

DRwBD

Deflection Routing with Backward Deflection

DRwoBD

Deflection Routing without Backward Deflection

DSF

Dispersion Shifted Fiber

DWDM

Dense WDM

EAP

Even Assignment Problem

EBvN

Efficient BvN

EBvN_FEC

EBvN with Filing Empty Cells

EDFA

Erbium-Doped Fiber Amplifier

EDF

de

Even Density distribution through gauging Frame

EDF

di

Even Distance distribution through gauging Frame

EF

Expedited Forwarding

EON

Elastic Optical Network

ES

Edge Switch

FCFS

First-Come-First-Served

FD

Fair Dissemination distribution

FDL

Fiber Delay Line

FDM

Frequency Division Multiplexing

FEC

Forward Error Correction

FEC

Forwarding Equivalent Class (in MPLS networks)

FF

First-Fit

FIFO

First-In-First-Out

FRWC

Full Range Wavelength Converter

FSC

Fiber-Switch-Capable

FTTH

Fiber-To-The Home

FTWC

Fixed-input/Tunable-output WC

FWC

Fixed Wavelength Converter

GF

Gauging Frame

GMPLS

Generalized Multi-Protocol Label Switching

GST

Guaranteed Service Transport

HCT

High Class Transport

HOPSMAN

High-performance Optical Packet-Switched MAN

HOS

Hybrid Optical Switching

HOTARU

Hybrid Optical neTwork ARchitectUre

HP

High-Priority

HSWC

Hybrid Shared Wavelength Conversion

HTDM

Hybrid TDM

IAS

Impairment-Aware Scheduling

ID

IDentification

ILP

Integer Linear Programming

IP

Internet Protocol

IPD

Intentional Packet Dropping

IPT

Immediate Packet Transmission

IPTV

Internet Protocol TV

ISA1

Ingress Switch Architecture 1 for class-based OPS networks

ISA2

Ingress Switch Architecture 2 for class-based OPS networks

LB

Load Balanced distribution index

LCR

Local Cyclic Reservation

LCR-SD

Local Cyclic Reservation with Source-Destination

LDP

Label Distribution Protocol

LER

Label Edge Router

LGRR

Loan-Grant-based Round Robin

LP

Low-Priority

LRWC

Limited-Range Wavelength Converter

LSC

Lambda-Switch-Capable

LSP

Label Switching Path

LSR

Label Switching Router

MAC

Media Access Control

MAN

Metropolitan Area Network

MBS

Merit-Based Scheduling

MEMS

Micro-Electro-Mechanical Systems

MF

Multi Fiber

MFAW

Multi Fiber + Additional Wavelengths

MI

Minimum Interference, Multilayer Interference

MING

Minimum Gap Queue

MINL

Minimum Length Queue

MP

Mid-Priority

MPBvN

Multi-Processor BvN

MPLS

Multi-Protocol Label Switching

M_PR

Modified Prioritized Retransmission

MPR

Multi-Path Routing

MQWS

Minimum Queue length Wavelength Selection

MUX

Multiplexer

MW-OPS

Multi-Wavelength Optical Packet Switching

NACK

Negative Acknowledge

NBR

Non-Blocking Receiver

NCPA

Non-Composite Optical Packet Aggregation

NCT

Normal Class Transport

NoD

No Deflection

NR

No Retransmission

NRP

Number-Rich Policy

NRPWC

Non-Recursive Parametric Wavelength Conversion

NWB-OPS

Non-Wavelength-Blocking OPS

NZDSF

Non-Zero Dispersion-Shifted Fiber

OBM

Optical Bandwidth Manager

OBS

Optical Burst Switching

OCGRR

Output-Controlled Grant-based Round Robin

OCS

Optical Circuit Switching

O/E/O

Optical/Electrical/Optical

OOFDM

Optical Orthogonal Frequency Division Multiplexing

OP

Optical Packet

OpMiGua

Optical Migration capable network with service Guarantees

OPS

Optical Packet Switching

ORION

Overspill Routing in Optical Networks

OSNR

Optical Signal-to-Noise Ratio

OTDM

Optical Time Division Multiplexing

OVP

OVerspill Packet

OXC

all-Optical Cross-Connect switch

PA

Packet Aggregation

PAU

Packet Aggregation Unit

PDP

Preemptive Drop Policy

PDU

Protocol Data Unit

PLR

optical Packet Loss Rate

PMD

Polarization Mode Dispersion

POADM

Packet Optical Add and Drop Multiplexers

PQOC

Probabilistic Quota plus Credit

PR

Prioritized Retransmission

PS

Packet Scheduler

PSC

Packet-Switch-Capable

PSK

Phase Shift Keying

PTES

Packet Transmission based on Scheduling of Empty Time Slots

PWC

Parametric Wavelength Converter

QAM

Quadrature Amplitude Modulation

QoS

Quality of Service

QoT

Quality of Transmission

QPSK

Quadrature Phase-Shift Keying

RIB

Reservation Induced Blocking

RNENF

Random choice among Neither Empty Nor Full queues

ROADM

Reconfigurable Optical Add/Drop Multiplexer

ROB

Removing of Overdue Blocks

RPWC

Recursive Parametric Wavelength Conversion

RR

Random Retransmission

RS

Reed-Solomon

RSA

Routing and Spectrum Assignment/Allocation

RSVP

Resource Reservation Protocol

SA

Spectrum Assignment/Allocation

SBvN

Separated BvN

SDU

Service Data Unit

SFD

Smoothed Flow Decomposition

SHP

Shortest Hop-Path

SLA

Service Level Agreement

SM/BE

Statistically Multiplexed Best Effort

SMF

Single-Mode Fiber

SM/RT

Statistically Multiplexed Real Time

SOA

Semiconductor Optical Amplifier

SPC WC

Single-Per-Channel Wavelength Converter

SPIL WC

Shared-Per-Input-Link Wavelength Converter

SPIW WC

Shared-Per-Input-Wavelength Wavelength Converter

SPL WC

Shared-Per-Link Wavelength Converter

SPN WC

Shared-Per-Node Wavelength Converter

SPOL WC

Shared-Per-Output-Link Wavelength Converter

SPOW WC

Shared-Per-Output-Wavelength Wavelength Converter

SPR

Shortest-Path Routing

SSMF

Standard Single-Mode Fiber

SWING

Simple Wdm rING

TCP

Transmission Control Protocol

TDM

Time Division Multiplexing

TFWC

Tunable-input/Fixed-output WC

TLWC

Two-Layer Wavelength Conversion

Tout

Timeout

TTL

Time-To-Live

TTWC

Tunable-input/Tunable-output WC

TWC

Tunable Wavelength Converter

VRP

Variety-Rich Policy

WAN

Wide Area Network

WAR

Wavelength Access Restriction

WB-OPS

Wavelength-Blocking OPS

WC

Wavelength Converter

WDM

Wavelength Division Multiplexing

WDS

Wavelength Delay Section

WRN

Wavelength Routed Network

wsc

Waveband-Switch-Capable

wss

Wavelength Selective Switch

wxc

Wavelength Cross-Connect

GLOSSARY

* Notation used in switch sizes, say a switch with a inputs and b outputs is denoted by a*b

x

mod

y

Remainder of x divided by y

Asynchronous OPS

Pure (non-slotted) OPS

Client packet

The upper layer packet arriving at an ingress switch from legacy networks

Conversion ratio

Ratio of total number of WCsused in an N*N OPS switch with W wavelengths to total number of wavelengths in the switch (i.e., N x W)

Core switch

An optical switch that performs switching in the optical domain

Drop link

f fibers connecting a core switch to an egress switch for delivering f optical packets on each wavelength from the core to the edge switch at the same time

Drop port

One fiber connecting a core switch to an egress switch for delivering one optical packet on each wavelength from the core to the edge switch

Egress switch

An edge switch with the function of receiving traffic from an optical network

FDL bank

A bank of FDL buffers that provides delay in range 0 to B x D, where D is a constant delay time and B is the buffer depth

Gbits/s

Gigabits per second

Ingress switch

An edge switch with the function of transmitting traffic to an optical network

Input port

An input fiber to a core switch from a neighbor edge/core switch in a single-fiber network

Input link

f fibers input to a core switch from a neighbor edge/core switch in a multi-fiber network

Legacy network

Any network (including an old network, an Ethernet network, a TCP/IP network, and a SONET/SDH network) connected to an edge switch

Local optical packet

The optical packet either added to an OPS switch by its local ingress switch, or dropped by the OPS switch to its local egress switch

max(

x, y

)

The larger value of x and y

Mbits

Megabits

min(

x

,

y

)

The smaller value of x and y

nf-slot-set

The set of n X / optical packets sent from n ingress switches on the same wavelength channel and on / fibers within a given time slot

nm

Nano meters

ns

Nano seconds

Optical packet

The packet transmitted by an ingress switch to an OPS network that may include one or more client packets

OP set

A set of optical packets transmitted at the same time slot over the available fibers/wavelengths in an ingress switch

OPS core switch

An optical switch that performs OPS switching functionality in the optical domain

Output port

An output fiber from a core switch to a neighbor edge/core switch in a single-fiber network

Output link

f fibers output from a core switch to a neighbor edge/core switch in a multi-fiber network

Slot set

Set of f × W rows in a column of a frame in frame-based scheduling

Synchronous OPS

Slotted OPS

Tbits/s Torrent

Terabits per second

Torrent

All the (class-based) traffic going to the same egress switch in an ingress switch. Therefore, Torrent-i traffic goes to egress switch i

Transit optical packet

The optical packet that passes through an OPS switch toward another OPS switch

Uniform selection

Uniform selection from a list with m items; i.e., selecting an item randomly with probability .

WC bank

A bank of wavelength converters with the same type